RU2594759C1 - Method and device for determining coordinates of a radio emission - Google Patents

Abstract

FIELD: radio engineering.

SUBSTANCE: invention relates to radio engineering and can be used for determining coordinates of radio-frequency sources in ultrashort-wave (VNF) and a microwave (SHF) ranges of radio waves using narrow-band signals. Specified result is achieved because the synthesis algorithm of a difference aperture is used, which allows to eliminate the effect of instability of the phase of the transmitter, and also to consider the modulation of RFS signal. Specified result is achieved also by optimization of flight route of carriers of main (MP) and external (EP) positions of the passive locator, as well as by the fact the ground station of management (GSM), by commands of which carry out simultaneous synchronous reception of signals of RFS by antenna-receiving modules MP and EP and formation of quadrature components of signal envelopes and their transmission to GSM together with data on time of reception signal and spatial position of phase centers of receiving antennas, formation on their basis of difference of trajectory values S(t_i) by pairwise multiplication of quadrature signal components S₁(t_i), received at MP at a time t_i with appropriate complex conjugate values of quadrature components of signal,

received in the EP at a time t_i, finding based on S(t_i) obtained at the interval of synthesizing I·Δt, location of RFS using method of matched processing. Method is realized using a device made in a certain manner.

EFFECT: achieved technical result - ensuring increase of accuracy of determining of coordinates of radio-frequency sources (RFS) in the VNF-SHF-ranges of radio waves.

5 cl, 14 dwg, 1 tbl

Description

The inventive objects are united by one inventive concept, relate to radio engineering and can be used in navigation, direction finding, location tools to determine the location of an a priori unknown source of radio emission (IRI).

A known method implemented in a movable direction finder described in US Pat. RF №2124222, IPC G01S 13/46, publ. 12/27/1998, it includes the reception of signals from radio sources in a given frequency band AF by a direction-moving detector in space, measurement of the primary spatial information parameters (PPIP) of the detected signals with simultaneous measurement of secondary parameters: PPIP measurement time, location coordinates and orientations (in the azimuth plane ) an antenna array of a mobile direction finder, converting the PPIP into spatial parameters: azimuth angle θ, θ = 0, 1, ..., 360 ° and elevation angle β, β = 0, 1, ..., 90 °. The analogue method allows you to determine the parameters of curved trajectories of the object.

However, the analogue has insufficient accuracy of measuring the coordinates of the IRI due to the fact that it implements two-stage processing of measurement results. At the first stage, at each jth point, j = 1, 2, ..., J, the spatial parameters θ _j and β _j are measured _, which at the second stage are used to calculate the location of the IRI. In the book (Kondratiev BC et al. Multiposition Radio Engineering Systems / BC Kondratiev, A.F. Kotov, L.N. Markov; Ed. By Prof. V.V. Tsvetnova. - M.: Radio and Communications, 1989, - 264 p.) It is shown that systems with two-stage processing give worse results than with optimal one-stage processing.

, а в процессе работы при обнаружении сигнала ИРИ на частоте

способ-аналог включает измерения ППИП на выходах A_m,l-ных антенных элементов (АЭ) решетки с одновременным измерением вторичных параметров, вычисление для каждого направления в горизонтальной плоскости разности между эталонными и измеренными значениями ППИП, возведение в квадрат полученных разностей и их суммирование, формирование матрицы измерений R_j(θ_c,n)_ν из сумм

, определение после выполнения J измерений ППИП минимальной суммы

в элементах матрицы измерений R_j(θ_c,n)_ν, принятие координат местоположения центра элементарной зоны привязки {X, Y}_n, соответствующие min

за координаты местоположения обнаруженного ИРИ.A known method for determining the coordinates of the IRI described in Pat. RF №2536609, IPC G01S 5/04, publ. 10/28/2014, bull. Number 36. At the preparatory stage, the analogue includes calculating the number N = S / S _{0 of} elementary binding zones, where S and S _0, respectively, the area of the control zone and the elementary binding zone, assigning to each elementary binding zone the serial number n, n = 1, 2, ..., N, determining the coordinates of the location of the centers of the elementary binding zones {X, Y} _n , calculating and storing the reference values of the IPPP at the outputs of the A _{m, l-} th antenna elements, where m, l = 1, 2, ..., M, m ≠ l, M> 2, relative to the directions of arrival of the test signal with a resolution of Δθ _k , k = 1, 2, ..., K; K · Δθ _k = 2π; moreover, PPIP are calculated for medium frequencies

, and in the process of detecting an IRI signal at a frequency

The analogue method includes measuring the PPIP at the outputs of the A _{m, l-} th antenna elements (AE) of the array with the simultaneous measurement of secondary parameters, calculating for each direction in the horizontal plane the difference between the reference and measured values of the PPIP, squaring the differences and summing them, the formation of the measurement matrix R _j (θ _{c, n} ) _ν from the sums

, determination after performing J measurements PPIP minimum amount

in the elements of the measurement matrix R _j (θ _{c, n} ) _ν , the adoption of the coordinates of the location of the center of the elementary binding zone {X, Y} _n , corresponding to min

for the location coordinates of the detected IRI.

The analogue allows to increase the availability and accuracy of determining the coordinates of the IRI due to the implementation of one-stage processing of the measurement results and placement of the direction finder on the flight-lifting facility (LPS), taking into account its spatial orientation.

However, the accuracy of determining the coordinates of Iran from the LPS in the wavelength range of 30-300 MHz remains low due to inconsistent dimensions of the direction-finding antenna system.

The closest in its technical essence to the claimed is a method for determining the coordinates of the source of radio emission in Pat. RF №2305851, IPC G01S 5/04, publ. September 10, 2007. The prototype includes receiving an IRI signal to antenna-receiving modules (APM) installed on two moving mechanically connected carriers and forming a narrow-base system of the main position (OP) and the remote position (VP) of a passive locator (PL), detecting IRI signals and determination of its carrier frequency, the formation of the quadrature components of the envelope of the IRI signal at the outputs of the APM during the movement of the OP and VP, repeated measurement over the range interval, which is the synthesis interval, of these quadrature components and their combination new memorization with the measurement time and the position of the phase center of the APM receiving antenna in the space of the OP and VP at the time of each measurement step of these envelopes with subsequent finding based on the data obtained on the synthesis interval, the location of the IRI.

The prototype method allows to increase the accuracy of determining the coordinates of the IRI through the use of remote points by increasing (matching) the direction finding base.

However, the prototype has disadvantages that limit its use. These include:

the relatively low accuracy of estimating the spatial parameters of the IRI signal due to an inconsistent (narrow-base) OP antenna and the lack of spatial orientation (the LPS drift angle is not taken into account) of the OP carrier;

the movement of OP and VP in space relative to the IRI is correlated and cannot be optimized with respect to accuracy characteristics;

unknown frequency offset between TAM and IRI is not taken into account;

phase instability in the receiving and transmitting paths limits the method for the time of coherent accumulation of the estimated signal;

relative complexity and significant cost of the meter (involves the use of a plane with significant dimensions as a carrier to accommodate direction-finding antennas and multi-channel equipment).

A device for determining the coordinates of a source of radio emission according to Pat. RF №2536609, IPC 5/04, publ. 12/27/2014, bull. Number 36. The analog device contains a spatial parameter determination unit, first, second, third, fourth and fifth shapers, first and second memory blocks, a radio navigator, an angular orientation device, a primary spatial information parameters measuring unit, a clock generator, an estimation unit, a determination unit coordinates and display unit, in a certain way interconnected. The device is located on a flying-lifting facility (airplane, helicopter) and provides increased accessibility of the IRI signals of the VHF-microwave frequency ranges and the accuracy of their location. However, due to the significant overall dimensions of the direction-finding antenna system of the block for determining spatial parameters and the difficulty of implementing the actual device for determining the coordinates of the IRI (overall weight characteristics), it makes it impossible to place it on unmanned aerial vehicles of medium and small classes. In addition, the use of analogue is limited due to the high cost of the carrier and its operation.

The closest in its technical essence to the claimed device for determining the coordinates of the IRI is a device according to Pat. RF №2550811, IPC G01S 13/46, publ. 05/20/2015, bull. Number 14.

The prototype device contains two or more unmanned aerial vehicles (UAVs) and a ground control station (NPU), each UAV containing a serially connected controller, steering gear and aerodynamic steering wheels, an autopilot, the group of information inputs of which are connected to the second group of information outputs of the controller, the first group of information inputs of which is connected to the group of information outputs of the autopilot, a propulsion system, the group of information inputs of which is connected to the third group of information ion outputs of the controller, the first transceiver module, the group of information inputs of which are connected to the fourth group of information outputs of the controller, the second group of information inputs of which is connected to the group of information outputs of the first transceiver module, serially connected video surveillance unit, the first storage device and transmitting module, navigation unit An UAV, the group of information outputs of which is connected to a second group of information inputs of the first storage device, and the NPU is made up comprising a first control unit in series for controlling the take-off, flight and landing of the UAV, a second transceiver model and a first information processing and display device, serially connected a second storage device made by L-channel, a recognition device made by L-channel, the second control unit, designed to set the source data and generate a command to determine the coordinates of the objects, and a second processing and display device information, the group of information outputs of which is the first output bus of the NPU, the second group of information inputs is combined with the second group of information inputs of the second control unit and the group of information outputs of the receiving module, made L-channel, the group of information inputs of the second storage device is the input bus of the NPU, the second output whose bus is connected to the second group of information outputs of the recognition device, the third group of information outputs of which is connected to the group sing address inputs of the second storage device.

The prototype device provides increased throughput due to more efficient detection and recognition of predetermined objects based on video images from the board of several UAVs, by implementing the "computer vision" procedure.

However, the prototype device also has a disadvantage associated with the low accuracy of determining the coordinates of objects due to non-optimal overall dimensions of the direction-finding antenna in the frequency range under consideration, which ultimately significantly increases the time required to detect the specified objects.

The purpose of the claimed technical solutions is to develop a method and device for determining the coordinates of the IRI, providing: improving the accuracy of the location of the IRI in the VHF-microwave frequency ranges through the use of the method of synthesis of differential aperture (CPA) and optimization of flight paths of carriers.

, принятыми на ВП в момент времени t_i, t_i=i·Δt, i=1, 2, …, I; Δt - шаг по времени, нахождение на основе данных S(t_i), полученных на интервале синтезирования I·Δt, местоположения ИРИ с применением метода согласованной обработки.In the claimed method, the goal is achieved by the fact that in the known method for determining the coordinates of a radio emission source, which consists in that they receive a signal from a radio source to antenna receiving modules mounted on two moving mechanically connected carriers and forming the main and remote positions of the passive locator, they detect a signal IRI and determine its carrier frequency, form during movement with the help of OP and VP quadrature components of the envelope of the IRI signal at the outputs of the APM with a frequency of F _ds , repeatedly but measured on the range interval, which is the synthesis interval, these quadrature components and they are jointly stored with the measurement time at the time of each measurement step of evaluating these envelopes, followed by the next location based on the data obtained on the synthesis intervals, the location of the IRI. Using N remote positions of passive locators, N≥1, based on separate carriers, form a ground control point (NPU), the commands of which provide simultaneous synchronous reception of the IRI signal by the antenna-receiving modules OP and VP and the formation of the quadrature components of the envelope of the signal and transmitting them respective communication channels to NPU together with data on the time t _i of the reception signal and the spatial position of the phase centers of the receiving antennas OP APM and EP joint orderly storage on quad values NPU Saturn signal components and time parameters, as well as temporal and spatial parameters corresponding OP and VI, forming on their basis of difference S (t _i) of the trajectory values by pairwise multiplication stored quadrature components of the signal S ₁ (t _i), taken at OD at point in time t _i , with the corresponding complex conjugate values of the quadrature components of the signal $$S_{}^{}$$$${}_2^{*}(t_i)$$

taken at the VP at time t _i , t _i = i · Δt, i = 1, 2, ..., I; Δt - time step, finding based on the data S (t _i ) obtained on the synthesis interval I · Δt, the location of the IRI using the consistent processing method.

At the main and remote positions, only one antenna-receiving module is used.

For coordinated processing of the measurement results, the received differential trajectory signal is multiplied by the reference function, which is a complex conjugate differential trajectory signal from the IRI located in the resolution element with the given coordinates, the signal is accumulated modulo during the synthesis time, normalized, and values characterizing the resolution elements are obtained, find the location of the IRI by searching for the resolution element with the largest given value.

The synchronization of measurement of parameters on the OP and VP is carried out autonomously by each medium using the time stamps of the satellite navigation system.

Thanks to the new set of essential features in the inventive method, using the differential aperture synthesis method, the frequency offset of the AMS and IRI, phase instability in the transmitting IRI, and phase modulation of the signal are eliminated, which improves the accuracy of determining the coordinates of the IRI.

The goal in the claimed device is achieved by the fact that in the known device, consisting of two or more identical unmanned aerial vehicles and a ground control point, each of the UAVs contains a serially connected controller, steering gear and aerodynamic steering wheels, an autopilot, the group of information inputs of which are connected to the second group of information outputs of the controller, the first group of information inputs of which is connected to the group of information outputs of the autopilot, propulsion system, the group of information inputs of which is connected to the third group of information outputs of the controller, the first L-channel transceiver module, the group of information inputs of which is connected to the fourth group of information outputs of the controller, the second group of information inputs of which is connected to the first group of information outputs of the first transceiver module, connected in series the first storage device and the transmitting module, the UAV navigation unit, the group of information outputs of which is connected to a second group of information inputs of the first storage device, and the NPU is made up comprising a series-connected first control unit for controlling the takeoff, flight and landing of the UAV, a second L-channel transceiver model and a first information processing and display device, connected in series to the L-channel receiving module, the second control unit, designed to set the source data and generate a command to determine the coordinates of the radio signal source and the second processing device and displaying information, the group of information outputs of which is the output bus of the ground control point, in addition to each UAV, one antenna-receiving module (APM) is introduced, a group of information outputs of each of which is connected to the first group of information inputs of the corresponding first storage device, and the group the control inputs are connected to the second group of information outputs of the first transceiver module, and a correlator, a group of information outputs of which horn is connected to the second group of information inputs of the second information processing and display device, and the group of information inputs is combined with the first group of inputs of the second control unit, the second group of outputs of which is connected to the second group of information inputs of the second transceiver module, the second storage device, the group of information inputs which is the second installation bus of the ground control point, and the group of information outputs is connected to the third group of inputs of the second device information processing and display, and the second group of information inputs of the second control unit is the first installation bus of the ground control point.

The listed new set of essential features due to the fact that new elements and connections are introduced, allows to achieve the purpose of the invention: to increase the accuracy of positioning of the IRI in the VHF-microwave frequency ranges due to the implementation of the method of synthesis of differential aperture in the meter.

The inventive objects are illustrated by drawings, which show:

in FIG. 1 - a generalized algorithm for determining the coordinates of a source of radio emission;

in FIG. 2 - a generalized synthesis algorithm for differential aperture;

in FIG. 3 is a generalized block diagram of a device for determining the coordinates of a radio emission source;

in FIG. 4 is a structural diagram of an antenna receiving module;

in FIG. 5 - procedure for tuning the receiving paths of the APM;

in FIG. 6 is a structural diagram of a second information processing and display device;

in FIG. 7 - the results of the first variant of the formation of the uncertainty function in the synthesis of differential aperture:

a) the trajectory of the phase centers of antennas 1 (OP) and 2 (VP) in the time interval t ₁ -t ₂ ;

b) the cross section of the FN at a level of 0.7 in the synthesis of differential aperture;

c) the cross-section of the FN during the synthesis of the aperture for trajectory 1 (OP);

d) the cross section of the DF during the synthesis of the aperture for trajectory 2 (VP);

in FIG. 8 - the results of the second variant of the formation of the uncertainty function in the synthesis of differential aperture:

a) the trajectory of the phase centers of antennas 1 (OP) and 2 (VP) in the time interval t ₁ -t2;

b) the cross section of the FN at a level of 0.7 in the synthesis of differential aperture;

c) the cross-section of the FN during the synthesis of the aperture for trajectory 1 (OP);

d) the cross-section of the FN during the synthesis of the aperture for trajectory 2 (VP);

in FIG. 9 - the results of the third variant of the formation of the uncertainty function in the synthesis of differential aperture:

a) the trajectory of the phase centers of the antennas OP and VP on the time interval t ₁ -t ₂ ;

b) the cross section of the FN at a level of 0.7 in the synthesis of differential aperture;

c) the cross-section of the FN during the synthesis of the aperture for trajectory 1 (OP);

d) the cross-section of the FN during the synthesis of the aperture for path 2 (VP);

in FIG. 10 - UAV motion paths relative to the IRI in a fixed coordinate system:

a) for experiments No. 1-6;

b) for experiment No. 7;

in FIG. 11 (1-7) - total uncertainty functions (step along x - 10 m, step along y - 5 m) and their resolution elements in FGC for elements 1-7, respectively;

in FIG. 12 shows the results of aperture synthesis for a carrier frequency of 30.5 MHz:

a) the trajectory of the UAV 1 and 2 relative to the IRI in the FSK;

b) UAV ground speeds;

c) the spectrum of the signal received on board the UAV 1;

d) the spectrum of the signal received on board the UAV 2;

d) the frequency of the received differential path signal (1) and the frequency of the reference differential path signal (2);

e) the phase difference between the reference and the received differential path signal;

g) the uncertainty function (step along x - 10 m, step along y - 5 m);

h) an element of permission under the Federal Grid Company;

in FIG. 13 shows the results of aperture synthesis for a carrier frequency of 199.5 MHz:

a) the trajectory of the UAV relative to the IRS in the FSK;

b) UAV ground speeds;

c) the spectrum of the signal received on board the UAV 1;

d) the spectrum of the signal received on board the UAV 2;

d) the frequency of the received differential path signal (1) and the frequency of the reference differential path signal (2);

e) the phase difference between the reference and the received path signals;

g) the uncertainty function (step along x = 10 m, step along y = 5 m);

h) permission element in the Federal Grid Company;

in FIG. 14 shows the results of aperture synthesis for a carrier frequency of 146 MHz:

a) the trajectory of the UAV relative to the IRS in the FSK;

b) UAV ground speed;

c) the spectrum of the signal received on board the UAV 1;

d) the spectrum of the signal received on board the UAV 2;

d) the frequency of the received differential path signal (1) and the frequency of the reference differential path signal 2;

e) the phase difference between the reference and the received differential path signals;

g) the uncertainty function (step along x = 10 m, step along y = 5 m);

h) permission element in the Federal Grid Company.

The invention consists in the following. Within the framework of the proposed materials, the emphasis is on determining the location of the IRI in the VHF-microwave frequency bands (30-300 MHz) using small aircraft, which is economically feasible.

Currently, implementations of phase-difference and difference-rangefinder-Doppler methods for determining coordinates based on small unmanned aerial vehicles (UAVs) are known (see Rembovsky AM and other Radio Monitoring - Tasks, Methods, Means / Ed. AM Rembovsky. - M. : Hotline-Telecom, 2010 .-- 624 p.). The phase-difference method involves the use of at least three APMs on board the UAV, which limits its use in the meter wavelength range due to the overall and weight characteristics. The use of the difference-rangefinder-Doppler method is limited by the class of broadband signals and the complexity of implementation.

For the mentioned initial data, it is preferable to use the method of passive aperture synthesis (PSA), which is implemented by moving one APM in space to build a large virtual aperture. At the same time, unlike a synthetic aperture radar, in passive synthesis there is no reference radio signal and a single radio receiving device is used (see Kondratenkov G.S. Radiovision. Radar systems for remote sensing of the Earth / G.S. Kondratenkov, A.Yu. Frolov. - M .: Radio engineering, 2005. - 368 p.). This method relates to single-channel correlation interferometric meters, where the physical separation of channels is replaced by time.

In the proposed method and device for improving the accuracy of determining the coordinates, the use of passive synthesis of a differential aperture is proposed, which allows to eliminate the frequency offset between the TAM and the IRI transmitter, the influence of the instability of the transmitter phase, and also take into account the modulation of the IRI signal. In addition, an increase in the accuracy of measurements is achieved by optimizing flight paths of carriers of OP and VP relative to IRI.

The implementation of the method is achieved by the following sequence of actions. Using APM OP and VP, placed on mobile LPS (UAV) (Fig. 1, 2), receive the signal of the IRI. At the same time, one APM is placed on each of the LPS. Received at time interval [t _0; t _c ] the high-frequency signal is converted into an electrical signal of intermediate frequency, sampled with a frequency of F _ds and quantized, form two sequences of samples of quadrature components at zero frequency. In total, I _SA = T _SA · F _{ds of} complex readings of the IRI radio signal during the synthesis of the aperture T _SA , T _SA = t _c -t ₀ measured at time t _i , t = i · Δt, t = 0, 1, ... , T _SA -1, Δt = 1 / F _SA .

причем F_ds>Fd, I_SA>N_SA.At the same time in the time interval [t ₀ ; t _c ] determine the location of the phase centers of the APM antennas (FCA). The measurement frequency F _{d is} selected from the condition for obtaining unambiguous direction finding results. To do this, the distance between the individual elements of the aperture should be less than half the length of the received radio wave. As the coordinate system, the Earth’s Greenwich geocentric coordinate system (E) can be used (see Wang WQ Multi-Antennas Synthetic Aperture Radar, Boca Raton, FL; CRC Press, Taylor & Francis, cop., 2013. - 438 p.), or local (L) for a given carrier navigation coordinate system (LSC). The center of the latter coincides with the coordinates of the PCA at the initial t ₀ moment of synthesis. The Y axis coincides with the carrier vector velocity vector at time t ₀ , the Z axis is upward along the geophysical vertical, and the X axis complements the system to the right. As a result, we have N _sa = T _SA · F _d samples of the PCA trajectory during the synthesis of the aperture, measured at time instants t _n , t _n = n / Fd,

moreover, F _ds > Fd, I _SA > N _SA .

As a rule, carrier navigation systems measure the location in the Earth’s Greenwich geocentric coordinate system (GCS), and in the LSC it is convenient to analyze the properties of a synthesized aperture antenna. To recalculate the coordinates of the PCA between the ZSC and the LSC, we assume that the Z axis of the ZSC is directed toward the reference meridian, the Y axis is directed along the axis of rotation of the Earth, the X axis complements the system to the right, and introduce the matrix

where cX = cos (X), sX = sin (X). Then the matrix of guide cosines for the transition from LSC to LSC will take the form:

where B _L , L _l - geodetic coordinates of the beginning of the LSC, Ψ _ν - the track angle at time t ₀ .

It is known that for the common-mode addition of radio signals in the elements of the antenna system, the error of the position of the points of the aperture relative to a given order λ / 8, where λ is the length of the radio wave, which corresponds to the error of measuring the phase of the signal π / 4, is permissible. In the proposed method, it is necessary to distinguish between errors in the knowledge of the initial position of the PCA at time t ₀ and errors in its position relative to the initial position during the synthesis time T _SA .

An error in the knowledge of the initial position of the PCA leads to an equal error in determining the location of the IRI, but does not affect the coherent accumulation of the radio signal in the aperture (see Kondratenkov G.S. Radiovision. Radar systems for remote sensing of the Earth / G.S. . - M .: Radio engineering, 2005. - 368 p.). Requirements for knowing the initial position of the FCA are determined on the basis of the conditions for ensuring the required accuracy in estimating the spatial parameters of the signal. The error, which is a linear incursion of the FCA coordinates during the synthesis of the aperture, caused by errors in estimating the displacement velocity, will entail a shift in the maximum of the uncertainty function without deteriorating the resolution of the meter (see ibid.). Therefore, the requirements for the frequency of measuring the location of the FCA follow from the conditions for ensuring the required direction finding accuracy.

Thus, in the proposed method for ensuring coherent accumulation of the radio signal in the aperture on the synthesis interval T _SA for the problem of passive location, the accuracy of reading the coordinates of the PCA relative to the linear incidence within the range of λ ± / 8 is taken as acceptable.

The measured values of the quadrature components of the signal received at the OD and VP, together with data on the spatial position of the FCA APM and the time of their measurement t _i and t _n, respectively, are transmitted to the NPCs through the corresponding communication channels. The signal data received at the test site is jointly stored (the values of the quadrature components of the signal of the corresponding item and their measurement time t _i , as well as the coordinates of the phase center of the APM antenna of the corresponding item and their measurement time t _n ).

Discrete readings of the quadrature components of the signal envelope, taken on the synthesis interval of the l-th APM from a stationary source with a wavelength of λ, can be represented as

U_l(i) - амплитуда сигнала, r_l(i) - расстояние от ИРИ до траектории перемещение ФЦА l-го АПМ в момент времени i,

- отстройка между l-м АПМ и ИРИ, Δt=1/F_ds - шаг по времени, φ_m(i) - фазовая модуляция сигнала ИРИ, δ_φИРИ(i) - нестабильность фазы передающего модуля ИРИ, δφ_l(i) - нестабильность фазы l-го АПМ, φ_ol - постоянный фазовый сдвиг для l-го АПМ. Из выражения (3) следует, что полезной информацией для определения местоположения ИРИ является составляющая фазы, вызванная изменением расстояния от ИРИ до АПМ. Для выделения полезной информации в предлагаемом способе предлагается выполнить перемножение сигналов, принятых разными АПМ:Where

U _l (i) is the signal amplitude, r _l (i) is the distance from the IRI to the trajectory, the movement of the FCA of the l-th APM at time i,

is the detuning between the lth APM and IRI, Δt = 1 / F _ds is the time step, φ _m (i) is the phase modulation of the IRI signal, δ _φIRI (i) is the phase instability of the transmitting IRI module, δφ _l (i) - the instability of the phase of the lth APM, φ _ol is the constant phase shift for the lth APM. From the expression (3) it follows that useful component for determining the location of the IRI is the phase component caused by a change in the distance from the IRI to the TMA. To highlight useful information in the proposed method it is proposed to perform the multiplication of signals received by different APM:

- комплексно сопряженный сигнал, принятый от ИРИ на втором носителе ВП.where S ₁ (i) is the signal received from the IRI on the first carrier OP,

- complex conjugate signal received from the IRI on the second carrier VP.

, где

- полоса принимаемого сигнала, с - скорость света. Например, для полосы

разница расстояний от носителей до ИРИ должна быть меньше 15 км. Невыполнение названного условия приводит к необходимости учета задержки между сигналами S₁(t) и S₂(t).In the expression (4), the assumption is made that the delay between the signals S ₁ (i) and S ₂ (i) can be neglected. This is true if the condition:

where

- band of the received signal, s - speed of light. For example, for a strip

the distance difference from carriers to Iran should be less than 15 km. Failure to fulfill the above condition leads to the need to take into account the delay between the signals S ₁ (t) and S ₂ (t).

Expression (4) for the resulting signal S (i) has the form:

- отстройка по частоте между первым и вторым АПМ, φ₀ - постоянный фазовый сдвиг.Where

- frequency offset between the first and second TMA, φ ₀ - constant phase shift.

From the expression (5) it can be seen that operation (4) eliminates the unknown detuning in the frequency of the IRI, the instability of the phase in the transmitting path of the IRI, as well as the phase modulation of the radio signal. The synchronization of the OP and VP receivers is carried out using second time stamps from the navigation satellite receiver, the accuracy of which is 50 ns. The latter are used in conjunction with highly stable generators, which are adjustable according to the second time stamp.

из чего следует, что полоса полезного сигнала определяется диапазоном доплеровских частот, присутствующих в траекторном сигнале. Поэтому частота дискретизации результирующего сигнала (4) может быть понижена до значения F_d.The resulting signal S (t) has a smaller frequency band than the original signals S _l (i) received by the TMA. Useful information lies in the phase component of the signal.

from which it follows that the band of the useful signal is determined by the range of Doppler frequencies present in the path signal. Therefore, the sampling frequency of the resulting signal (4) can be reduced to a value of F _d .

In this case, the difference trajectory signal is understood as the samples of the resulting signal (4) taken at time instants t _n ,

Q (n) = S (t _n ), t _n = n / F _d ,

At the next stage, a coordinate system is defined in which the difference aperture (S) will be synthesized. As the latter, a fixed (F) relative to the earth Cartesian coordinate system (FGC), the location of which is set by the operator, can be chosen. In this case, the Y axis is directed northward along the tangent to the geographic meridian, the Z axis is directed upward along the geodetic vertical, and the X axis complements the system to the right. In this case, taking into account (1), the matrix of guide cosines for the transition from FSK to ZSK has the form:

where b_F, L_F - geodetic coordinates of the beginning of the FSK. Alternatively, one of the LSCs for the carriers used may be selected. The matrix of guide cones for the transition from LSC to FGC has the form

Since the coordinate system can be set at the first (preliminary) stage of work, in the process of work only the coordinates of its beginning are set.

Then, the trajectories of two FCA are recalculated into a single coordinate system.

If the trajectories of the PCA are measured in the GCC, and the FSK (S = F) is selected as the coordinate system for the synthesis of the difference aperture (5), then the recalculation is performed in accordance with the expression (6)

- координаты l-го ФЦА в ЗСК в момент времени n,

- координаты центра системы координат для синтеза в ЗСК.where l is the number of the carrier,

- the coordinates of the l-th FCA in the KCC at time n,

- the coordinates of the center of the coordinate system for synthesis in the KCC.

At the next stage, the working area for searching the location of the IRI is set. This operation in some cases (if there is a priori information about the IRI) can be one of the first at the preparatory stage to increase the speed of the proposed method (similar to the known solutions proposed in Pat. RF No. 2296341, 2327186 and others). In the general case, and for the convenience of consideration, the assignment of the coordinate system used in the measurements and the working area of the IRI search is carried out jointly by the operator. For this purpose the coordinates of the working zone of search center (X _{c,, Y c, Z c)} , the maximum deviation from the center of the three axes of the selected coordinate system (M _x, M _y, M _z), space quantization step for each of the axes (Δ _x , Δ _y , Δ _z ) is set from the condition of ensuring the required accuracy and resolution of the meter (direction finder). The number of gradations along the coordinate axes is

где

- операция округления до целого.

Where

- rounding operation to the whole.

Space points within the working area in accordance with the selected sampling steps along each axis are numbered: k _x = 0, 1, ..., N _x along the X axis, k _y = 0, 1, ..., N _y along the Y axis, k _z = 0, 1, ..., N _z along the Z axis. Moreover, the (k _x , k _y , k _z ) -th point has the coordinates x _k = Δ _x · Δk _x + x _s -M _x , y _k = Δ _y K _y + y _c -M _y , z _k = Δ _z k _z + z _c -M _z . Total obtained K _{= N x · N y · N} z bins, wherein k-th element is given resolution three-dimensional vector

The space quantization step along each axis must be less than the resolution of the meter along the corresponding axis.

It is known that the resolution along the line of motion of the carrier (in azimuth) and subject to the passage of the radio signal in one direction is determined by the expression (see Kondratenkov G.S. Radiovision. Radar systems for remote sensing of the Earth / G.S. Kondratenkov, A.Yu. Frolov. - M: Radio engineering, 2005. - 368 p.)

wherein R _n - slant range from the carrier to the IRI, d - resolution synthetic aperture, θ _n - viewing angle IRI. Obviously, the resolution depends on the distance between the carrier and the IRI, as well as on the viewing angle. The minimum achievable resolution in one of the coordinates for the aperture synthesized on the l-th carrier within the working area determines as

- минимальная наклонная дальность от l-го носителя до ИРИ.Where

- the minimum slant range from the l-th carrier to the IRI.

Providing the possibility of a twofold improvement in resolution in the case of the synthesis of a differential aperture for an arbitrary flight path of the lth carrier, the quantization step of the space along the horizontal axes can be set

определяется какIn the next step of the method, reference (reference) signals are generated for all K resolution elements with a given wavelength λ. Reference (reference) trajectory signal from a monochromatic stationary source with a wavelength λ located in the kth resolution element with coordinates

defined as

- координаты l-го ФЦА в системе координат (S) в момент времени n. Опорный (эталонный) разностный траекторный сигнал для k-го элемента разрешения из совокупности К находят из выраженияWhere

- coordinates of the l-th FCA in the coordinate system (S) at time n. The reference (reference) difference trajectory signal for the k-th resolution element from the set K is found from the expression

Next, the processing of the path signal is carried out. For each k-th resolution element, the characteristic value is calculated:

Based on the obtained values of A _k proceed to the construction of a spatial image.

The set of values of A _k is a spatial uncertainty function (FN), which characterizes the mismatch of the received differential trajectory signal from the IRI and the reference (reference) difference trajectory signal calculated for known trajectories of the involved FCA and known coordinates of the IRI. For each point in space along the vertical axis z _k = Δ _z · k _z + z _c -M _z , k _z = 0, 1, ..., N _{z, a} spatial image of the FN is built on a plane passing through z _k . We denote this two-dimensional FN

и соответствующее ему

при котором двумерная ФН обладает хорошим разрешением и наибольшей величиной. На втором этапе находят местоположение ИРИ путем поиска элемента разрешения с наибольшей величиной A_K At the final stage, they start processing the FN, which is performed in two stages. On the first of them choose the value

and corresponding to it

in which a two-dimensional photonic crystal has a good resolution and the largest magnitude. At the second stage, the location of the Iran by finding the resolution element with the largest value A _K

In case of poor resolution along one of the horizontal coordinates (x, y), the IRI location can be fixed in two ways. Draw a line running along the ridge of the fn, i.e. get the direction to Iran on a plane (bearing Iran). In this case, finding several bearings allows you to determine the location of the IRI as the point of intersection. Either add (superimpose) several FN obtained on different trajectories, and determine the location of the IRI in accordance with (13).

The device for determining the coordinates of the source of radio emission (see Fig. 3) contains two or more identical UAVs 1 ₁ -1 _m and a ground control station 2, with each UAV 1 ₁ -1 _m made in series containing a controller 1.6, a steering gear 1.7 and aerodynamic steering wheels 1.9, autopilot 1.2, the group of information inputs of which is connected to the second group of information outputs of the controller 1.6, the first group of information inputs of which is connected to the group of information outputs of the autopilot 1.2, propulsion system 1.1, the group of information of the input inputs of which is connected to the third group of information outputs of the controller 1.6, the first L-channel transceiver module 1.8, the group of information inputs of which is connected to the fourth group of the information outputs of controller 1.6, the second group of information inputs of which is connected to the first group of information outputs of the first transceiver module 1.8 connected in series with the antenna-receiver module 1.3., the first storage device 1.4 and the transmitting module 1.10, the navigation unit UAV 1.5, a group of information outputs which is connected to the second group of information inputs of the first storage device 1.4, and the group of control inputs of the antenna-receiving module 1.3 is connected to the second group of information outputs of the first transceiver module 1.8, and the ground control point 2 is made containing the first control unit 2.1, the second L connected in series -channel transceiver module 2.2 and a first information processing and display device 2.7, serially connected L-channel receiving module 2.3, a second control unit 2.8 and a second e information processing and display device 2.5, the information output group of which is the output bus 2.6 of the ground control point 2, the correlator 2.4, the information output group of which is connected to the second group of information inputs of the second information processing and display device 2.5, and the group of information inputs is combined with the first group the inputs of the second control unit 2.8, the second group of outputs of which is connected to the second group of information inputs of the second transceiver module 2.2, the second memory 2.9, the group of information inputs of which is the second installation bus 2.11 of the ground control point 2, and the group of information outputs is connected to the third group of inputs of the second information processing and display device 2.5, and the second group of information inputs 2.10 of the second control unit 2.8 is the first installation bus of the ground control room 2.

The inventive device for determining the coordinates of the source of radio emission works as follows (see Fig. 2 and 3).

где

- операция округления до целого.At the preparatory stage, the range of operating frequencies ΔF and UAV flight paths 1 ₁ and 1 ₂ , the values of F _ds and F _d , T _ds , T _{n are} set on the first input bus 2.10 of the ground control point 2. On the second input bus 2.11, a digital map of the control area, the coordinates of the center of the control area (X _s , Y _c , Z _c ), the maximum disconnection from the center of the control area along three axes (M _x , M _y , M _z ), the space quantization step along each of the axes (Δ _x , Δ _y , Δ _z ) from the condition of ensuring the required accuracy and resolution of the direction finder, the number of gradations along the coordinate axes

Where

- rounding operation to the whole.

k=0, 1, …К-1.Space points within a given control zone in accordance with the selected sampling steps along each axis are numbered: k _x = 0, 1, ..., N _x along the X axis, k _y = 0, 1, ..., N _y along the Y axis, k _z = 0, 1, ..., N _z along the Z axis. Moreover, the (k _x , k _y , k _z ) th point has the coordinates: x _k = Δ _x · k _x + X _with -M _x ; y _k = Δ _y · k _y + Y _c -M _y , z _k = Δ _z · k _z + Z _c -M _z . In total, it turns out K = N _x · N _y · N _z resolution elements, while the Kth resolution element is specified by a three-dimensional vector

k = 0, 1, ... K-1.

The named values are recorded in the second storage device 2.9, which is a buffer memory. During operation of the inventive device, the named values can be adjusted.

The quantization of the space of the control zone and its description can also be performed in another known manner, described in detail in US Pat. RF №№2283505, 2327186.

The take-off, flight and landing of UAVs 1 ₁ and 1 _{2 are} controlled from the first automated workstation of the ground control station 2, consisting of the first control unit 2.1, the second transceiver module 2.2 and the first information processing and display device 2.7. This operation is carried out on the first low-speed duplex radio channel at frequencies of 0.9-0.92 GHz using modules 1.8 and 2.2. UAV flight routes 1 ₁ and 1 _{2 are} determined based on their predetermined control zone in accordance with the recommendations formed above. The control signals of block 2.1, by analogy with the prototype, through the modules 2.2 and 1.8 _l are fed to the input of the controller 1.6 _l , l = 1,2, where they are converted to the form necessary to control the propulsion system 1.1. Next, from the output of the 1.6 _l unit they follow to the group of inputs of the propulsion system 1.1 _l and through the steering gear 1.7 _l change the angles of the wings, the configuration of their surface and other parameters of the UAV 1 _l motion control. Autopilot 1.2 _l provides the necessary stabilization of the position of the UAV 1 _l in space at a height set by the unit 2.1, parry wind disturbances, movement along a given route, etc. The impact of the autopilot 1.2 _l on the propulsion system 1.1 _l and through the steering gear 1.7 _l - on the aerodynamic wheels 1.9 _{l is} carried out through the controller 1.6 _l . The latter generates the necessary control commands for the UAV functional units based on the initial data of block 1.2 _l . It should be noted that the first automated workstation is able to simultaneously control the flight of up to four Orlan-10 UAVs.

Directly participate in coordinate measuring radiation source on board the UAV January _1, 1 ₂ are antenna-receiver module 1.3 _l, first memory 1.4 _l, UAV navigation unit 1.5 _l and a transmitting unit 1.10 _l, and the ground control point 2 - the second workstation place in the composition of the receiving module 2.3, the correlator 2.4, the second device for processing and displaying information 2.5, the second control unit 2.8 and the second storage device 2.9.

With APM and 1.3 ₁ 1.3 ₂ OP and VI, respectively (see. FIG. 4) disposed on the UAV carry IRI reception signal. On each of the carriers (for example, Orlan-10), one APM is placed. This circumstance made it possible to sharply reduce the overall dimensions of the nuclear submarines and the energy consumed by them, and as a result, the possibility of their placement on small UAVs.

Received by the antenna element (AE) of the block 1.3 _l at the time interval [t ₀ ; t _c ] the high-frequency signal is converted into an electrical signal of intermediate frequency, sampled with a frequency F _ds and quantized. As AE use a whip antenna of an agreed length. Due to the fact that the working frequency band is quite wide (30-300 MHz), an additional introduction of an antenna amplifier into the 1.3 _l module was required. Then, in block 1.3 _l , two sequences of samples of quadrature components at zero frequency are formed. In total, I _sa = T _SA · F _{ds of} complex readings of the IRI radio signal during the synthesis of the aperture T _SA , T _SA = t _c -t ₀ measured at time t _i , t = iΔt, t = 0, 1, ... T _SA -1, Δt = 1 / F _SA . The measured values of the quadrature components of the signal are transmitted to the first group of information inputs together with the values of the time t _i . Here they are paired (S _l (t _i ) and t _i ) are stored.

At the same time using block 1.5 in the time interval [t ₀ ; t _c ] determine the location of the phase centers of the APM 1.3 _l antennas in the Greenwich (E) geocentric coordinate system. Hereinafter, FCA will mean the location of the AE attachment point to the UAV body. The measurement frequency F _d is selected from the condition of obtaining unambiguous results of direction finding, and, therefore, the distance between the individual elements of the aperture should be less than half the length of the received radio signal. The measured coordinates of the UAV 1 _l and the time of their measurement are jointly transferred to the second group of information inputs of the block 1.4 _l , where they are stored. It should be noted that the block 1.4 _l serves as a buffer storage device. Two pairs of measured parameters (quadrature components of the signal and their measurement time, UAV location coordinates and the time of their measurement) are fed to the group of information inputs of the transmitting module 1.10 and then via the high-speed simplex channel at frequencies of 2-2.5 GHz to the second AWP NPU 2. Implementation block 1.5 _l compared with the same block of the prototype is greatly simplified. This is due to the fact that the claimed device does not require information on the drift angle of the UAV 1 _l due to the fact that a pin with a circular radiation pattern is used as the antenna of the 1.3 _l unit.

с борта l-го БПЛА 1_l через блок 2.3 поступают на соответствующую группу информационных входов коррелятора 2.4. Здесь

и

- соответственно широта, долгота и высота l-го БПЛА в момент времени t_n. Аналогичная информация на соответствую группу информационных входов блока 2.4 поступает с другого БПЛА 1₁₊₁. В функцию блока 2.4 входит выполнение операции (4). В результате устраняется неизвестная отстройка по частоте приемного тракта блока 1.3 и анализируемого ИРИ, нестабильность фазы в передающем тракте этого ИРИ, а также фазовая модуляция радиосигнала. Синхронная работа блоков 1.3_l и 1.3_l+1 осуществляется с помощью секундных меток времени, принимаемых блоками 1.5_l и 1.5_l+1. Последние дополнены высокостабильными генераторами, запускаемыми этими метками.The measured time for synthesis T _SA values of the estimated parameters _{(S l (t i),} t il and coordinates of UAV

from the board of the l-th UAV 1 _l through block 2.3 go to the corresponding group of information inputs of the correlator 2.4. Here

and

- respectively, the latitude, longitude and height of the l-th UAV at time t _n . Similar information to the corresponding group of information inputs of block 2.4 comes from another UAV 1 _{1 + 1} . The function of block 2.4 includes the execution of operation (4). As a result, an unknown frequency offset of the receiving path of block 1.3 and the analyzed IRI is eliminated, phase instability in the transmitting path of this IRI, as well as phase modulation of the radio signal. The synchronous operation of 1.3 _l and 1.3 _{l + 1} blocks is carried out using second timestamps received by 1.5 _l and 1.5 _{l + 1} blocks. The latter are supplemented by highly stable generators triggered by these tags.

The results are received on the second group of inputs of the second device for processing and displaying information 2.5. At the same time, the values of the quadrature components of the signals from both UAVs 1 _l and 1 _{l + 1} are fed to the corresponding inputs of the first group of inputs of the second control unit 2.8. In block 2.8, the analysis of received quadrature signals (threshold processing) is performed for the simultaneous presence of signals from the sides of both UAVs. If a signal is received by both modules 1.3 and 1.3 _{l + 1} at the output of block 2.8, a control signal is generated to block 2.5 to implement the difference aperture synthesis. Otherwise, when signal reception is provided by only one TMA 1.3 _l , block 2.8 signals the need to change the flight route of the corresponding carrier (UAV).

(13).The functions of the second information processing and display device (see Figs. 2 and 6) include generating a synthesized aperture based on Q (n) (4), calculating the signals of the reference trajectory signals in accordance with (10) and (11), performing coordinated processing trajectory signals (12), the construction of the spatial spectrum with its subsequent two-stage processing in order to find the resolution element with the largest value of the spatial uncertainty function

(13).

The results of determining the coordinates are reflected on the monitor of block 2.5 against the background of a digital map of a given area and simultaneously arrive in the specified format on the output bus 2.6 of the NPU 2. Using block 2.8, the simultaneous tuning of the receiving paths of the APM 1.3 ₁ and 1.3 ₂ is controlled.

All functional elements and blocks of the proposed device are widely covered in the literature and are commercially available.

As a UAV 1 ₁ -1 _L, it is advisable to use the Special Technological Center, a serial company, the city of St. Petersburg, the Orlan-10 UAV (see http://bp-la.ru/bpla-orlan- 10/). The UAV payload weight is 5 kg, the launch method is from a collapsible catapult, landing is by parachute. The UAV airspeed is 90-150 km / h, the maximum flight duration is 16 hours, the maximum range is 600 km, and the maximum altitude is 5 km.

The antenna-receiving module 1.3 is designed to receive IRI signals in the frequency range 2-30-300 MHz, convert them to an intermediate frequency, for example, 90 MHz, with subsequent conversion of the received signals to digital form (see Fig. 4 and 5). Its implementation is known and does not cause difficulties. Module 1.3 contains a series-connected pin antenna 1.3.1, an antenna amplifier and a splitter 1.3.2, a block for receiving and converting 1.3.3, and a block of analog-to-digital converters 1.3.4, the group of information outputs of which is a group of information outputs of the antenna-receiving module 1.3, the block of reference frequencies 1.3.5, the first group of inputs of which is the control input of the antenna-receiver module 1.3, the second group of inputs is the reference input of the antenna-receiver module 1.3, the first, second and third outputs of the block 1.3.5 are connected to the reference odes respective receiving channels receiving unit and converting 1.3.3, and a fourth output connected to the reference input unit of analog-digital converters.

в 60 МГц обеспечивается компактной настройкой трех приемных каналов по 20 МГц каждый в соответствие с фиг. 5. Такую настройку каналов блока 1.3.3 обеспечивают опорные напряжения, формируемые блоком 1.3.5. Перестройка блока 1.3.3 в рабочей полосе ΔF (30-300 МГц) осуществляется также блоком 1.3.5 по командам второго блока управления 2.8. Синхронность перестройки АПМ 1.3₁ и 1.3₂ в полосе ΔF осуществляется по секундным меткам, поступающим на опорные входы модулей 1.3 (блоки 1.3.5).The operation of the antenna-receiving module is as follows. The signal received by antenna 1.3.1 is amplified in block 1.3.2 and, through a splitter, is fed to the inputs of a three-channel block for receiving and converting 1.3.3. The latter is designed to simultaneously receive radio signals in the 60 MHz band, provide preliminary selection of signals and convert them to an intermediate frequency, for example, 90 MHz. Strip

60 MHz is provided by compact tuning of three receiving channels of 20 MHz each in accordance with FIG. 5. Such adjustment of the channels of block 1.3.3 is ensured by the reference voltages generated by block 1.3.5. The restructuring of block 1.3.3 in the working band ΔF (30-300 MHz) is also carried out by block 1.3.5 according to the instructions of the second control unit 2.8. The synchronization of the tuning of the APM 1.3 ₁ and 1.3 ₂ in the ΔF band is carried out by second marks arriving at the reference inputs of modules 1.3 (blocks 1.3.5).

Received in block 1.3.3 and converted signals from the outputs of the receiving channels are fed to the corresponding inputs of the three-channel block of analog-to-digital converters 1.3.4. Here, the received signals are decomposed into quadratures and digitized. As a result, a digital stream of quadratures received in the 60 MHz band is formed at the output of module 1.3.

The implementation of all elements of module 1.3 is known and does not cause difficulties. The receiving and converting unit 1.3.3 is designed to simultaneously receive signals in a wide 60 MHz frequency band and convert them to an intermediate frequency, for example, 90 MHz. Its implementation is known and does not cause difficulties (see Fomin NN, Bug NN and others. Radio receivers: Textbook for high schools. - 3rd ed., Stereotype. - M .: Hot line-Telecom, 2007 . - S. 520; Golovin OV Radio receivers, - M.: Hot line - Telecom, 2004).

The block of analog-to-digital converters 1.3.4 can be implemented on serial products manufactured by ZETlab Studio (http://www.zetlab.ru/catalog/). Other implementations of block 1.3.4 are also possible (see "Professional Equipment and Technologies" http://www.protehnology.ru/page/about/).

The block of reference frequencies 1.3.5 is designed to form a highly stable signal with a frequency of 120 MHz. It contains a reference generator that provides the formation of a highly stable analog signal with a frequency of 10 MHz (performed on the basis of a DDS synthesizer).

From the output of the synthesizer, a signal with a level of - 4 dBm is fed to an amplifier with a gain of 14 dB and then to a square wave driver with a frequency of 120 MHz. It is advisable to manufacture the latter on an ADCMP 551 comparator from Analog Devices (http://www.analog.com/media/en/technical-documentation/data-sheets/ADCMP551_552_553.pdf).

The antenna amplifier can be implemented using a product from IKUSI SBA 110, and the splitter: TLPG-3E from LANS. As 1.3.1, a matched asymmetric vibrator is used.

The first 1.4 _l storage device intended for the orderly storage of the quadrature components of the signal S _l (t _i), together with values for their preparation time t _i, and UAVs coordinate (X, Y, Z) _n and time of measurement t _n. It is a buffer memory device and is easily implemented on reprogrammable read-only memory devices (KM 1609 series) and discrete elements of the TTL series (see Large Integrated Circuits of Storage Devices: Reference Book / A.Yu. Gordonov et al .; Edited by A.Yu. Gordonova. - M.: Radio and Communications, 1990. - 288 p.)

The implementation of the navigation block 1.5 is known and does not cause difficulties. To ensure higher accuracy of positioning (3-5 m) block 1.5 can be implemented in accordance with Pat. RF No. 2553270, 2371733 or 2374659.

The Orlan-10 UAV control is implemented from the first AWP (blocks 2.1, 2.2, and 2.7) via a low-speed communication channel at frequencies of 900–920 MHz in the mode of pseudo-random tuning of the operating frequency. On this channel (blocks 2.2 and 1.8), the flight route, flight altitude and flight order are set: passage at altitude or barrage, etc. Control information is generated using block 2.1, which can be used as a laptop. In addition, block 2.8 generates commands for the restructuring of the APM 1.3 UAV l ₁ and 1 ₂ (in the general case, 1 ₁ -1 _L ).

The results of measurements on 2 sides NPU UAV January ₁ 1 ₂ fed by respective high-speed channels at frequencies of 2000-2500 MHz for the second workstation. The information transfer rate in the channels is 4 Mbps. The communication range depends on the flight altitude and local conditions and averages 100-130 km. Using the second AWP, the detection, recognition and determination of the coordinates of the specified IRI are carried out.

Correlator 2.4 is designed to perform calculations in accordance with expression (4). Its implementation is known and does not cause difficulties (see, for example, Pat. RF No. 1840069, IPC G06F 17/15; Zalmazon L.A. Fourier, Walsh, Harra and their application in management, communications and other fields. - M. : Science, 1989 .-- 496 s).

The second storage device 2.9 is designed to store the initial data: the coordinates of the center of the search region (X _s , Y _c , Z _c ), the maximum deviation from the center of the search region (M _x , M _y , M _z ), the quantization step of the search space (Δ _x , Δ _y , Δ _z ), the number of gradations along the coordinate axes (N _x , N _y , N _z ), a digital map of the search area (control zone). These data are received before the start of operation of the device via the second input bus 2.11 of the ground control point 2. They are necessary to perform the calculations performed by block 2.5 in the process of operation of the inventive device. The implementation of block 2.9 is known and does not cause difficulties (see Lebedev, O.N. Memory chips and their application. - M .: Radio and communications, 1990. - 160 s .; Large integrated circuits of memory devices: reference book / A.Yu. Gordonov et al .; Edited by A.Yu. Gordonov and Yu.N. Dyakov. - M.: Radio and Communications, 1990. - 288 p.).

The second device for processing and displaying information 2.5 (see Fig. 6) is designed to determine the coordinates of the IRI by implementing operations in accordance with expressions (10) - (13). On an ongoing basis, the coordinate system in which the difference aperture will be synthesized is written in the algorithm of operation of block 2.5. As the latter, it is advisable to use a Cartesian coordinate system (F) fixed relative to the earth. The location of the beginning of which is set by the operator through the second control unit 2.8. In this case, the Y axis is directed northward along the tangent to the geographic meridian, the Z axis is directed upward along the geodetic vertical, and the X axis complements the system to the right. It is known that the carrier’s navigation system (block 1.5 _l ) measures the location in the Earth coordinate system (E), then the PCA trajectories of two APMs are recalculated in block 2.5 in a single coordinate system (S) in accordance with expression (6)

- координаты l-го ФЦА в земной (Е) системе координат в момент времени n.l is the number of the carrier,

- coordinates of the l-th FCA in the earth (E) coordinate system at time n.

In addition, to calculate the reference signals in accordance with (10) and (11), the third group of inputs of block 2.5 receives (from the group of information outputs of block 2.9) the initial data: (X _s , Y _c , Z _c ), (M _x , M _y , M _z ), (Δ _x , Δ _y , Δ _z ), (N _x , N _y , N _z ). In addition to this, to ensure the clarity of the indication of the results of determining the coordinates of the IRI, a third carat of the control zone (search area) is fed to the third group of inputs of block 2.5.

The second device for processing and displaying information 2.5 (see Fig. 6) contains in series the first correlator 2.5.5, the second adder 2.5.6, the divider 2.5.7, the memory block 2.5.8, the analysis block 2.5.9 and the indication block 2.5. 10, the first group of inputs of which is the group of outputs of the second processing and indicating device 2.5 and the output bus 2.6 of NPU 2, the second group of inputs of block 2.5.10 is the third group of inputs of block 2.5, the series-connected block of squaring 2.5.1, the first adder 2.5. 2, square root 2.5.3 extraction block and 2.5.4 multiplier , the group of information outputs of which is connected to the group of inputs of the divider of block 2.5.7, the first group of inputs of the first correlator 2.5.5 is the second group of inputs of the second device for processing and displaying information 2.5, the first computer 2.5.11, the second computer 2.5.12 and the second correlator 2.5.13, the group of outputs of which is connected to the second group of information inputs of the first correlator 2.5.5, the second group of information inputs of the multiplier 2.5.4 is combined with the groups of control inputs of the first 2.5.2 and second 2.5.6 sum mators and the second group of information inputs of the first calculator 2.5.11 and is the first group of inputs of the second information processing and display device 2.5, the first group of information inputs of the block 2.5.11 is combined with the group of information inputs of the squaring block 2.5.1 and the group of information inputs of the first correlator 2.5.5 and is the second group of inputs of block 2.5, and the third group of information inputs of block 2.5.11 is combined with the second group of information inputs of block 2.5.10.

The operation of the device for processing and displaying information 2.5 is carried out under the control of block 2.8.

The normal mode of operation of the inventive device provides for the synthesis of a differential aperture while simultaneously receiving NPU 2 signals from two spatially separated APM 1.3 ₁ and 1.3 ₂ .

с выходов коррелятора 2.4 поступают на первую группу входов первого коррелятора 2.5.5. Кроме того, значение Q(n) одновременно поступает на информационные входы блока возведения в квадрат 2.5.1 и первого вычислителя 2.5.11. С помощью блоков 2.5.1-2.5.4, 2.5.5-2.5.7 и 2.5.11-2.5.13 для каждого элемента разрешения зоны контроля вычисляется характеризующая его величина A_k в соответствии с (12). При этом с помощью блоков 2.5.5, 2.5.6 и 2.5.11-2.5.13 определяется модуль суммы корреляционных функций

для n=0, 1, …, N_SA. Эталонный разностный траекторный сигнал P_k(n) находится с помощью блоков 2.5.11-2.5.13. В первом вычислителе 2.5.11 осуществляется пересчет траекторий двух ФЦА в единую систему координат (S) в соответствии с (6). С учетом того, что выполняют переход от земной системы координат (Е) к фиксированной относительно земли декартовой системе координат (S) выражение (6) преобразуется в (14). Для реализации данной функции на первую группу информационных входов блока 2.5.11 с первой группы входов второго блока управления 2.8 поступают геодезические координаты начала ФСК (S). На второй группе его информационных входов присутствуют координаты l-го ФЦА в земной (Е) системе координат в момент времени n

Полученные на выходе блока 2.5.11 значения

поступают на группу информационных входов второго вычислителя 2.5.12. В функции последнего входит вычисление опорных (эталонных) сигналов с длиной волны λ. для каждого элемента разрешения заданной зоны контроля z_l,k(n) в соответствии с (10). Далее в корреляторе 2.5.13 определяется разностный траекторный сигнал P_k(n) в соответствии с (11). Значение

поступает на вторую группу информационных входов первого коррелятора 2.5.5.Difference trajectory signals Q (n) = S (t _n ) taken at time t _n , t _n = n / Fd,

from the outputs of the correlator 2.4 go to the first group of inputs of the first correlator 2.5.5. In addition, the value of Q (n) simultaneously enters the information inputs of the squaring block 2.5.1 and the first calculator 2.5.11. Using blocks 2.5.1-2.5.4, 2.5.5-2.5.7 and 2.5.11-2.5.13 for each resolution element of the control zone, the characteristic value A _k is calculated in accordance with (12). Moreover, using the blocks 2.5.5, 2.5.6 and 2.5.11-2.5.13, the modulus of the sum of the correlation functions is determined

for n = 0, 1, ..., N _SA . The reference difference trajectory signal P _k (n) is found using blocks 2.5.11-2.5.13. In the first calculator 2.5.11, the trajectories of two FCA are recalculated into a single coordinate system (S) in accordance with (6). Taking into account that the transition from the Earth's coordinate system (E) to the Cartesian coordinate system (S) fixed relative to the earth is performed, expression (6) is converted to (14). To implement this function, the first group of information inputs of block 2.5.11 receives the geodetic coordinates of the beginning of the FSK (S) from the first group of inputs of the second control block 2.8. The second group of its information inputs contains the coordinates of the l-th FCA in the earth (E) coordinate system at time n

The values obtained at the output of block 2.5.11

arrive at the group of information inputs of the second calculator 2.5.12. The functions of the latter include the calculation of reference (reference) signals with a wavelength of λ. for each resolution element of a given control zone z _{l, k} (n) in accordance with (10). Then, in the correlator 2.5.13, the difference path signal P _k (n) is determined in accordance with (11). Value

arrives at the second group of information inputs of the first correlator 2.5.5.

Blocks 2.5.1-2.5.4 are intended to determine the value necessary to perform the normalization operation in expression (12).

At the output of the divider 2.5.7, the value A _{k is formed} that characterizes the k-th element of the resolution of the control zone. The values A _k , k = 0, 1, ... K-1 obtained by the above algorithm are stored in the corresponding cells of the memory block 2.5.9. Finding the location of the IRI is carried out by searching for the resolution element with the largest given value

using the analysis unit 2.5.9. The results of measurements of the coordinates of the IRI are fed to the group of inputs of the display unit 2.5.10 and are highlighted on the monitor against the background of a digital map of a given area. In addition, the measurement results in a given format are sent to the output bus 2.6 NPU 2.

If necessary, adjustment of reception paths and APM 1.3 ₁ 1.3 ₂ in the frequency range ΔF control unit 2.8 is formed corresponding to the command coming through blocks 2.2 and 1.8 on board UAV (block 1.3.5).

In the event of a situation when the reception of signals is provided by only one APM 1.3 _l , the control unit 2.8 generates information for the operator about the need to change the flight route of the corresponding UAV.

The implementation of all elements of block 2.5 is known and does not cause difficulties. To reduce the overall dimensions and current consumption, the blocks from 2.5.1 to 2.5.13 should be implemented on a specialized processor TMS320c6416 (see TMS320c6416: http://www.ti.com/lit/ds/sprs226m/sprs226m.pdn. Block operation algorithm 2.5 will result in Fig. 2.

The second control unit 2.8 is designed to control the operation of the APM 1.3 / (using it, values F _ds , T _SA , F _d , N _{SA are set} , controls the tuning of the receiving paths in the frequency band ΔF) and the second information processing and display device 2.5 (sets the start point coordinates (B _F , L _F , 0), parameter N _SA . In addition, block 2.8 provides a decision on the current reception of signals of one or both TMAs. The implementation of the block is known and does not cause difficulties. It can be implemented on a microprocessor assembly with sufficient speed ( see Shevkoplyas B.V. micro rotsessornye structure, engineering solutions: A Handbook - 2nd Edition, revised and enlarged - M .: Radio and communication, 1990 - 512).....

In the limited liability company “Special Technological Center”, St. Petersburg, a prototype of the proposed device was performed.

As the block for receiving and converting 1.3.3, the “Module for receiving and converting” was used, developed by STTs LLC and received the name UIES 468151.013. The latter is a three-channel radio receiver with a bandwidth of 20 MHz for each channel. Provides simultaneous reception of signals in the 60 MHz band. As a block of reference frequencies 1.3.5, the “Module of 10/120 MHz frequency generators” was used, which received the name UIES 467871.006, developed by STTs LLC. Blocks 2.4, 2.5, 2.8 and 2.9 were simultaneously implemented on a personal computer. As the minimum requirements for it, you can present the following: Core i 5 processor 2000 MHz, 1 GB of RAM, 200 MB of free space on your hard drive. Software component: Windows XP SP2 and higher, NetFrame Work 4.0 library, digital terrain map with terrain information and a format compatible with Panorama Group maps.

An experimental verification of the proposed method and device for determining the coordinates of the IRI. For this purpose, together with the above-mentioned elements of the device’s breadboard model, the Orlan-10 UAV manufactured by STC LLC in St. Petersburg was used. The signal sources used were TR 600s, VX-6R radios and a Marconi Instruments SG 2022s generator (frequency range 10 kHz - 1 GHz). The geodetic coordinates of the sources were known with high accuracy. In all experiments, for convenience, the beginning of the FSK was combined with the coordinates of the IRI. The latter provided the emission of radio signals at various frequencies with the most common types of modulation for the VHF-microwave ranges. During the experiments, two UAVs moved in different directions (on the sides of the square) at a distance of 4 km from the IRI at an altitude of 1 km with an average speed of 25 m / s.

An analysis was performed to determine the optimal mutual trajectories of UAV movement relative to the IRI. From the theory of classical synthesis of aperture (SA) (see Kondratenkov G.S. Radio-vision. Radar systems for remote sensing of the Earth / G.S. Kondratenkov, A.Yu. Frolov. - M: Radio engineering. 2005. - 368 p.) that the resolution of the latter in various coordinates depends on the UAV flight path. In the general case, SA provides spatial selection in all coordinates (x, y, z), however, its effectiveness is different and is determined by the rate of measurement of the phase term

where r ₀ (t) is the distance from the origin to the antenna trajectory at time t, r _ρ (t) is the distance of a point object with coordinate ρ to the antenna trajectory at time t.

In the synthesis of a difference aperture, spatial selection is determined by the rate of change of the phase term of the form:

where (*) _i refers to the trajectory of the i-th antenna, i = 1,2. Thus, if both receiving antennas move relative to the IRI during aperture synthesis, then the spatial selection efficiency will depend not only on the trajectory of the receiving antennas, but also on the direction of their mutual motion.

It follows from (16) that the choice of the flight paths of the UAVs of OP and VP allows one to achieve both an improvement in spatial resolution in comparison with the SA, and its deterioration.

Studies have shown that the best results are achieved when two UAVs move on opposite sides of the square around the IRI in opposite directions. This route provides good resolution in both coordinates in the horizontal plane. In FIG. 7.a shows one of the segments of this route (time interval t ₁ -t ₂ ), and in FIG. 7.b shows the resolution element obtained for the CPA method (section of the FN module at the level of 0.7). In FIG. 7.c and 7.d, the resolution elements for each trajectory are shown separately. From their consideration it can be seen that for this flight path of the UAV OP and VP, the resolution by the CPA method is two times better in both coordinates than the CA approach gives. The flight paths of the UAV OP and VP can be carried out on one side of the IRI. In this case, the UAV flight paths should be significantly spaced in space. The distance between the sides should be commensurate with the range to Iran. In FIG. Figure 8 shows one of the segments of this route along with resolution elements for CPA and CA methods. Another effective approach to solving this problem is the movement of two UAVs on the adjacent sides of the square. In FIG. Figure 9 shows one of the segments of this route along with resolution elements for CPA and CA methods.

As an option that gives a negative result, the movement of two UAVs along close (like the prototype) trajectories at the same speed at a distance much shorter than the distance to the IRI. In this case, the CPA method does not provide spatial selection.

During the experiments, the accuracy characteristics of the proposed method and device for determining the coordinates of the IRI were evaluated (see table. 1).

During experiments 1-6, two UAVs moved around Iran on opposite sides of the square in different directions at a distance of 4 km and an altitude of 1 km with an average ground speed of 25 m / s. The trajectories of UAV 1 and UAV 2 lasting 10 minutes (for experiment No. 1) are shown in FIG. 10.a.

The trajectories show the time in seconds from the start of the experiment. In experiment No. 7, UAV movement was carried out on adjacent sides of the square (see 10.b.)

The duration of each of experiments 1-6 was 10 minutes, experiment 7 lasted 5 minutes. The location error was determined as the distance from the maximum of the total FN (obtained by superimposing all FN calculated on the trajectory) to the known location of the IRI. The resulting errors in determining the location of the IRI are given in table. 1. In FIG. 11 shows the obtained total FN for experiments 1–7, as well as resolution elements in the FGC (step along x - 10 m, step along y - 5 m). In all figures, “+” indicates the location of the IRI, “•” - maximum fn. From the presented results it follows that the proposed method allows you to determine the location of the IRI at a distance of 4 km with high accuracy (measurement error for various types of modulation in the claimed frequency range does not exceed 7 m.)

With a continuous IRI signal (using a signal generator), the coherent accumulation time (aperture synthesis time) is limited by the accuracy of the PCA tracking and phase instabilities in the receiving channels. In the case of using radio stations, the aperture synthesis time is also limited by the duration of the signal transmission from the IRI. Radio stations turned on for an average of 20 seconds every 20 seconds.

In experiments, it was believed that the height of the IRI is known (located on the earth's surface).

In FIG. Figures 12-14 show the results of a single synthesis of difference apertures in experiments 1, 6, and 7.

For a carrier frequency of 30.5 MHz, the coherent accumulation time, determined by the accuracy of the PCA tracking and phase instabilities in the receiving channels, was 100 seconds. An example of one of the synthesized difference apertures for a continuous signal with AM modulation (experiment 1) is shown in FIG. 12.

In FIG. 12.a shows segments of UAV trajectories on which a differential aperture was synthesized, and in FIG. 12.b their UAV travel speed. On this segment lasting 100 seconds, UAV 1 was moving at an average speed of 22 m / s, and UAV 2 was moving at an average speed of 15 m / s. In FIG. 12.c, d show the spectra of signals received by the APM of two UAVs. In turn, in FIG. 12.d illustrates the frequency of the differential trajectory signal (1) received on two UAVs, and the frequency of the reference differential trajectory signal (2) obtained using (10) and (11) for the known coordinates of the IRI and the measured FCA trajectories. The phase difference between the reference and received path signals is shown in FIG. 12..e. For this example (step along x - 10 m, step along y - 5 m) in FIG. 2.g shows the obtained FN, and in FIG. 12.c depicts the permission element in the FSK.

For the carrier frequency 199.5 MHz, the coherent accumulation time, determined by the accuracy of the PCA tracking and phase instabilities in the receiving channels, was 15–20 seconds. An example of one of the synthesized difference apertures for a signal with a single-band modulation (experiment 6) is presented in FIG. 13.

For the carrier frequency of 146 MHz, the coherent accumulation time, determined by the accuracy of the PCA tracking and phase instabilities in the receiving channels, was 30-35 seconds. An example of one of the synthesized difference apertures during experiment 7 is shown in FIG. fourteen.

Thus, an experimental verification confirmed the possibility of achieving a positive effect.

Claims (5)

1. A method for determining the coordinates of a radio emission source, including receiving a signal from a radio emission source (IRI) to antenna receiving modules (APM) mounted on two moving mechanically connected carriers that form the main (OP) and remote (VP) position of the passive locator (PL), detection of the IRI signal and determination of its carrier frequency, the formation of the quadrature components of the envelope of the IRI signal at the outputs of the TMA with a frequency of F _ds during the movement with the help of OP and VP, repeated measurement over the range interval, which is the interval m of synthesis, these quadrature components and their joint storage with the measurement time at the time of each beat of the estimation of these envelopes, followed by finding on the basis of the data obtained at the synthesis intervals, the location of the IRI, characterized in that they use remote control locations of passive locators, N≥1, based on separate media, form a ground control point (NPU), the commands of which carry out simultaneous synchronous reception of the IRI signal by the antenna-receiving modules OP and VP and form a quad Saturn components envelope signal and transmitting them to the appropriate communication channels to NPU together with a signal receiving time data t _i and the spatial position of the phase centers of receive antennas TMA OP and VI together and orderly stored on NPU value quadrature signal components and time parameters, and also the temporal and spatial parameters corresponding to the OP and VP, form on their basis the differential trajectory values S (t _i ) by pairwise multiplication of the memorized quadrature components of the signal S ₁ (t _i ) received at the OD at time t _i , with the corresponding complex conjugate values of the quadrature components of the signal $$S_2^{*}(t_i)$$

taken at the VP at time t _i , t _i = i · Δt, i = 1, 2, ..., I; Δt is a time step, found on the basis of the data S (t _i ) obtained on the synthesis interval I · Δt, the location of the IRI using the consistent processing method, and all N remote positions of passive locators, N> 1, are based on separate carriers. 2. The method according to p. 1, characterized in that at the main and remote positions only one antenna-receiving module is used. 3. The method according to p. 1, characterized in that for the coordinated processing of the measurement results, the received differential path signal is multiplied by a reference function, which is a complex conjugate difference path signal from the IRI located in the resolution element with the given coordinates, the signal is accumulated modulo during the synthesis time, normalize, obtain the values characterizing the resolution elements, find the location of the IRI by searching for the resolution element with the largest given value. 4. The method according to p. 1, characterized in that the synchronization of the measurement of parameters on the OP and VP is carried out independently by each medium using time stamps of a satellite navigation system. 5. A device for determining the coordinates of a radio emission source, consisting of two or more identical unmanned aerial vehicles (UAVs) and a ground control station (NPU), each UAV containing a serially connected controller, steering gear and aerodynamic steering wheels, an autopilot, the group of information inputs of which are connected with the second group of information outputs of the controller, the first group of information inputs of which is connected to the group of information outputs of the autopilot, propulsion system, information group of the input inputs of which is connected to the third group of information outputs of the controller, the first L-channel transceiver module, the group of information inputs of which is connected to the fourth group of information outputs of the controller, the second group of information inputs of which is connected to the first group of information outputs of the first transceiver module, connected in series to the first storage device and a transmitting module, a UAV navigation unit, the group of information outputs of which is connected to the second group information inputs of the first storage device, and the NPU is made up comprising a series-connected first control unit for controlling the takeoff, flight and landing of the UAV, a second L-channel transceiver module and a first information processing and display device, series-connected L-channel receiver module, a second block control, designed to set the source data and the formation of the team to determine the coordinates of the source of the radio signal and the second processing device and displayed information, the group of information outputs of which is the output bus of the ground control point, characterized in that in addition to each UAV, one antenna-receiving module (APM) is introduced, a group of information outputs of each of which is connected to the first group of information inputs of the corresponding first storage device, and the group of control inputs is connected to the second group of information outputs of the first transceiver module, and a correlator, a group of information outputs the dow of which is connected to the second group of information inputs of the second information processing and display device, and the group of information inputs is combined with the first group of inputs of the second control unit, the second group of outputs of which is connected to the second group of information inputs of the second transceiver module, the second storage device, the group of information the inputs of which is the second installation bus of the ground control point, and the group of information outputs is connected to the third group of inputs of the second processing and displaying device, and a second group of information inputs of the second control unit is a first mounting rail ground control points.

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